Method for operating at least one electric machine

Abstract

A method for operating at least one electric machine that is designed to drive a vehicle, in which a value is determined for at least one operating parameter of the vehicle, wherein a change is predicted for the torque of the at least one electric machine at a target time point from the value of the at least one operating parameter, wherein a current for a magnetization of the at least one electric machine prior to the target time point is set at a value, wherein the value of the current for the magnetization at the target time point is changed and adapted.

The invention claimed is: 
     
       1. A method for operating a vehicle and designing at least one electric machine for driving of the vehicle, comprising:
 monitoring a time curve of a value for at least one operating parameter of the vehicle during a time interval before a starting time point; 
 predicting a change of a torque of the at least one electric machine for a target time point from the time curve of the value of the at least one operating parameter before the starting time point; 
 determining the value for at least one operating parameter of the vehicle at a starting time point; 
 setting a current for a magnetization of the at least one electric machine at a required value of the current for the magnetization at an intermediate time point prior to the target time point; and 
 adapting the required value of the current for the magnetization at the target time point, 
 wherein at least one of a slip of at least one wheel of the vehicle and a load of at least one axle of the vehicle is determined as the value of the at least one operating parameter. 
 
     
     
       2. The method as claimed in  claim 1 , wherein, based on the value of the at least one operating parameter, a probability is determined for the change in the torque for the target time point, wherein the current for the magnetization is set if the probability is at least as great as a threshold value provided for this. 
     
     
       3. The method as claimed in  claim 1 , in which the value for the at least one operating parameter is detected with at least one sensor of the vehicle. 
     
     
       4. The method as claimed in  claim 1 , which is carried out for at least one electric machine that is designed as an asynchronous machine or externally excited synchronous machine. 
     
     
       5. A system for operating at least one electric machine that is designed to drive a vehicle, wherein the system comprises:
 a control device that is designed to monitor a time curve of a value for at least one operating parameter of the vehicle during a time interval before a starting time point and predict a change in a torque of the at least one electric machine for a target time point based on the time curve of the value for the at least one operating parameter of the vehicle before the starting time point, wherein the control device is furthermore designed to determine the value for at least one operating parameter of the vehicle at a starting time point and cause a current for a magnetization of the at least one electric machine, at an intermediate time point prior to the target time point, to be set at a required value and the required value of the current for the magnetization at the target time point to be changed, 
 wherein at least one of a slip of at least one wheel of the vehicle and a load of at least one axle of the vehicle is determined as the value of the at least one operating parameter. 
 
     
     
       6. The system as claimed in  claim 5 , further comprising:
 at least one power electronics unit, which is coordinated with the at least one electric machine, and which is designed to provide the at least one electric machine with the current for the magnetization, wherein the control device is designed to assign the required value of the current for the magnetization to the at least one power electronics unit. 
 
     
     
       7. The system as claimed in  claim 5 , further comprising:
 at least one sensor that is designed to detect the value of the at least one operating parameter of the vehicle and provide the value to the control device. 
 
     
     
       8. The system as claimed in  claim 6 , further comprising:
 at least one sensor that is designed to detect the value of the at least one operating parameter of the vehicle and provide the value to the control device.